class DB():
    """
    选择数据库
    """
    def __init__(self,db):
        self.db=db

    def chose(self):
        return self.db

class SQL():
    """
    绑定SQL语言模板
    """
    def __init__(self):
        pass

    def oracle_tmp(self):
        pass

    def mysql_tmp(self):
        pass

    def dm_tmp(self):
        pass

    def sql_server_tmp(self):
        pass

class Table:
    """
    表结构
    """
    def __init__(self):
        pass

    def column(self):
        pass

    # def check(self):
    #     # 约束
    #     pass

class Column(Table):
    """
    行约束
    """
    def __init__(self):
        pass

    def check(self):
        # 约束
        pass

class Logs:
    """
    日志模块
    """
    def __init__(self):
        pass

    def error_log(self):
        # 错误日志
        pass

    def event_log(self):
        # 事件日志
        pass

if __name__ == "__main__":
    pass